3. Summary File Format

The current version of the summary file format is 5.0.

/

Attributes:
  • filetype (char[]) – String indicating the type of file.
  • version (int[2]) – Major and minor version of the summary file format.
  • openmc_version (int[3]) – Major, minor, and release version number for OpenMC.
  • git_sha1 (char[40]) – Git commit SHA-1 hash.
  • date_and_time (char[]) – Date and time the summary was written.

/geometry/

Attributes:
  • n_cells (int) – Number of cells in the problem.
  • n_surfaces (int) – Number of surfaces in the problem.
  • n_universes (int) – Number of unique universes in the problem.
  • n_lattices (int) – Number of lattices in the problem.

/geometry/cells/cell <uid>/

Datasets:
  • name (char[]) – User-defined name of the cell.
  • universe (int) – Universe assigned to the cell. If none is specified, the default universe (0) is assigned.
  • fill_type (char[]) – Type of fill for the cell. Can be ‘material’, ‘universe’, or ‘lattice’.
  • material (int or int[]) – Unique ID of the material(s) assigned to the cell. This dataset is present only if fill_type is set to ‘normal’. The value ‘-1’ signifies void material. The data is an array if the cell uses distributed materials, otherwise it is a scalar.
  • temperature (double[]) – Temperature of the cell in Kelvin.
  • translation (double[3]) – Translation applied to the fill universe. This dataset is present only if fill_type is set to ‘universe’.
  • rotation (double[3]) – Angles in degrees about the x-, y-, and z-axes for which the fill universe should be rotated. This dataset is present only if fill_type is set to ‘universe’.
  • lattice (int) – Unique ID of the lattice which fills the cell. Only present if fill_type is set to ‘lattice’.
  • region (char[]) – Region specification for the cell.

/geometry/surfaces/surface <uid>/

Datasets:
  • name (char[]) – Name of the surface.
  • type (char[]) – Type of the surface. Can be ‘x-plane’, ‘y-plane’, ‘z-plane’, ‘plane’, ‘x-cylinder’, ‘y-cylinder’, ‘z-cylinder’, ‘sphere’, ‘x-cone’, ‘y-cone’, ‘z-cone’, or ‘quadric’.
  • coefficients (double[]) – Array of coefficients that define the surface. See <surface> Element for what coefficients are defined for each surface type.
  • boundary_condition (char[]) – Boundary condition applied to the surface. Can be ‘transmission’, ‘vacuum’, ‘reflective’, or ‘periodic’.

/geometry/universes/universe <uid>/

Datasets:
  • cells (int[]) – Array of unique IDs of cells that appear in the universe.

/geometry/lattices/lattice <uid>/

Datasets:
  • name (char[]) – Name of the lattice.
  • type (char[]) – Type of the lattice, either ‘rectangular’ or ‘hexagonal’.
  • pitch (double[]) – Pitch of the lattice in centimeters.
  • outer (int) – Outer universe assigned to lattice cells outside the defined range.
  • universes (int[][][]) – Three-dimensional array of universes assigned to each cell of the lattice.
  • dimension (int[]) – The number of lattice cells in each direction. This dataset is present only when the ‘type’ dataset is set to ‘rectangular’.
  • lower_left (double[]) – The coordinates of the lower-left corner of the lattice. This dataset is present only when the ‘type’ dataset is set to ‘rectangular’.
  • n_rings (int) – Number of radial ring positions in the xy-plane. This dataset is present only when the ‘type’ dataset is set to ‘hexagonal’.
  • n_axial (int) – Number of lattice positions along the z-axis. This dataset is present only when the ‘type’ dataset is set to ‘hexagonal’.
  • center (double[]) – Coordinates of the center of the lattice. This dataset is present only when the ‘type’ dataset is set to ‘hexagonal’.

/materials/

Attributes:
  • n_materials (int) – Number of materials in the problem.

/materials/material <uid>/

Datasets:
  • name (char[]) – Name of the material.
  • atom_density (double[]) – Total atom density of the material in atom/b-cm.
  • nuclides (char[][]) – Array of nuclides present in the material, e.g., ‘U235’.
  • nuclide_densities (double[]) – Atom density of each nuclide.
  • sab_names (char[][]) – Names of S(\(\alpha,\beta\)) tables assigned to the material.

/nuclides/

Attributes:
  • n_nuclides (int) – Number of nuclides in the problem.
Datasets:
  • names (char[][]) – Names of nuclides.
  • awrs (float[]) – Atomic weight ratio of each nuclide.

/tallies/tally <uid>/

Datasets:
  • name (char[]) – Name of the tally.